Earthquarke prediction method and system thereof

ABSTRACT

Vehicles ( 1 - 1 ) or ships ( 1 - 2 ) each carry a magnetic force line sensor ( 11 ), a GPS position detector ( 12 ), and a data transmitter ( 13 ) and travel within an observation area transmitting magnetic field data and position data of each point to an earthquake prediction center ( 4 ). A telluric current induction field estimation unit ( 43 ) of the earthquake prediction center ( 4 ) estimates telluric current induction fields based on the observation data that it receives and collects. A telluric current estimation unit ( 44 ) estimates telluric currents based on the results of estimating the telluric current induction fields. A telluric current induction field intensity change pattern generation unit ( 45 ) generates patterns that indicate the change over time of the intensity of telluric current induction fields. An earthquake prediction unit ( 46 ) analyzes the state of distribution of the telluric currents and the patterns of change in the intensities of the telluric current induction fields and estimates a seismofocal zone, seismic intensity, and time of occurrence of a seismic event.

TECHNICAL FIELD

The present invention relates to an earthquake prediction method andsystem, and more particularly to an earthquake prediction method andsystem for measuring the magnetic field of each point within anobservation area to predict earthquakes.

BACKGROUND ART

The Japanese archipelago is situated on volcanic chains, and theoccurrence of a massive earthquake disaster is therefore a major concernin the oceans to the east, southeast and south, not to mentionthroughout the archipelago. To protect the lives and property ofcitizens from earthquake disasters, more suitable measures must be takennot only for systems for recovery following an earthquake, but forearthquake prediction, and for this purpose, the establishment of alow-cost, and moreover, highly accurate and effective earthquakeprediction technology is urgently required.

From ancient times, many examples of precursors of impending earthquakeshave been reported, such as the agitated behavior of catfish or theincreased activity of rats. In addition, several days before the GreatHanshin-Awaji (Kobe) Earthquake and Fire of January 1995, local amateurradio operators observed radio-wave abnormalities, and a phenomenonknown as an “earthquake cloud” was witnessed by many people.

It is believed that the occurrence of such radio-wave abnormalities and“earthquake clouds” result from some form of influence of telluriccurrents that are in turn generated by the piezoelectric effectresulting from the collision of tectonic plates.

The prediction of earthquakes by observing the amount of rotation of apermanent magnet that is suspended from a thread has been disclosed (forexample, in Japanese Patent Laid-Open Publication No. H11-258353).

However, the prediction of earthquakes with high accuracy by observingchanges in telluric current would necessitate the establishment of alarge number of closely-spaced observation facilities over an extensiveobservation area. As an example, earthquake prediction in the easternseaboard region of Japan would require an observation system coveringseveral hundred kilometers square.

With the current financial difficulties faced by national and municipalgovernments, such an establishment of a large number of observationfacilities would be a tremendous burden, and the costs for maintainingand operating the observation system would render the realization ofsuch a system highly problematic.

DISCLOSURE OF THE INVENTION

It is an object of the present invention to provide an earthquakeprediction method and system for collecting magnetic field data atnumerous points within an observation area at low cost, and moreover,within a short time period to thus enable accurate earthquakeprediction.

In the earthquake prediction method of the present invention, magneticfields are measured at various points within an observation area to bothestimate telluric current induction fields and to thus estimate telluriccurrents; and the state of the telluric currents within the observationarea and the change of the telluric currents over time are then analyzedto estimate a seismofocal zone, a time of occurrence of a seismic event,and seismic intensity.

In addition, a magnetic field noise component is eliminated from theobserved magnetic fields, the amount of divergence of the direction ofthe magnetic fields from the direction of true north at observationpoints from which this magnetic field noise component has beeneliminated is found, the telluric current induction fields are thenestimated based on the vector difference between the observed magneticfields from which the magnetic field noise component has been eliminatedand a geomagnetic vector that has been corrected to true north.

Further, the estimated telluric current induction fields are plotted ona map; the telluric currents are estimated by both joining points on themap at which geomagnetic abnormalities are noted and applying theright-handed screw rule; and the region in which the estimated telluriccurrent is concentrated is estimated to be a seismofocal zone.

Still further, past data of telluric current induction field intensitiesat specific observation points are gathered and a telluric currentinduction field intensity change pattern that indicates changes overtime is generated; and this pattern is then compared and collated withpast telluric current induction field intensity change patterns thathave been stored to estimate the time of occurrence and seismicintensity of a seismic event.

The earthquake prediction system of the present invention is providedwith: mobile units such as vehicles or ships, each unit carrying amagnetic force line sensor for supplying as output magnetic field datathat indicate the direction and intensity of lines of magnetic force, aGPS position detector for receiving radio waves of a GPS satellite andsupplying as output position data that indicate position, and a datatransmitter for transmitting these data; and an earthquake predictioncenter for collecting these data of various points that are transmittedby the mobile units that travel within an observation area and for thenimplementing earthquake prediction.

In addition, the earthquake prediction center includes: a data receiverfor receiving data that have been transmitted from the mobile units byway of a communication network and an antenna; a data storage unit forretaining and storing various data such as map data and data that havebeen received by this data receiver; a telluric current induction fieldestimation unit for estimating telluric current induction fields basedon map data and data that have been retained and stored in this datastorage unit; a telluric current estimation unit for estimating telluriccurrents based on the telluric current induction fields that have beenestimated; a telluric current induction field intensity change patterngeneration unit for accumulating transitions over time of the telluriccurrent induction field intensities and then generating change patterns;and an earthquake prediction unit for analyzing the telluric currentsthat have been estimated and the change patterns of the telluric currentinduction field intensities to estimate a seismofocal zone, seismicintensity, and time of occurrence of a seismic event.

Alternatively, when a mobile unit is provided with a car navigationsystem, the position data of the car navigation system may be usedinstead of data from a GPS position detector.

In addition, magnetic force line sensors and communication equipment maybe installed in preselected existing fixed structures within theobservation area, and the communication equipment may transmit themagnetic field data output of the magnetic force line sensors andinformation indicating the installation positions to the earthquakeprediction center by way of an existing communication network.

Further, a magnetic force line sensor and GPS position detector may beincorporated in, for example, a mobile telephone, and the mobiletelephone may use its own communication capabilities to transmitobservation data to the earthquake prediction center.

Still further, acceleration sensors may be provided in existing fixedstructures such that magnetic field data are transmitted when theacceleration sensors detect earthquake motion; or acceleration sensorsmay be provided in mobile units or in mobile telephones such thatmagnetic field data are transmitted when an acceleration sensor detectsa stationary state of at least a fixed time interval.

According to the present invention, by installing magnetic force linesensors, GPS position detectors, and data transmitters in, for example,vehicles or ships that travel within an observation area, collecting atan earthquake prediction center the magnetic field data at each pointwithin the observation area, and analyzing the telluric currentinduction fields and telluric currents that are estimated based on themagnetic field data, accurate earthquake prediction can be realized at alow equipment cost without necessitating the installation of measurementequipment at a multiplicity of points.

In addition, by establishing magnetic force line sensors at preselectedexisting structures within an observation area and then transmittingmagnetic data to an earthquake prediction center by way of an existingcommunication network, or alternatively, by establishing magnetic forceline sensors in devices such as a mobile telephones and thentransmitting magnetic data to the earthquake prediction center, theobservation data of a multiplicity of points within an observation areacan be collected at a low equipment cost to realize accurate earthquakeprediction.

Further, the installation of a magnetic force line sensor together withan acceleration sensor whereby observation data are automaticallytransmitted when the acceleration sensor detects earthquake motionenables the collection of magnetic field data at the time of theoccurrence of foreshocks that precede a main shock and thus allowsobservation data to be obtained that are effective in earthquakeprediction.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing an embodiment of the presentinvention;

FIG. 2 is a view showing a model of telluric current in the vicinity ofa seismofocal zone preceding the occurrence of an earthquake;

FIG. 3 shows the earthquake prediction operation of earthquakeprediction center 4 that is shown in FIG. 1;

FIG. 4 shows the estimation of a telluric current induction field;

FIG. 5 shows an example of the estimation of a telluric current;

FIG. 6 shows an example of telluric current induction fields andtelluric currents that have been measured;

FIG. 7 shows an example of telluric current induction fields andtelluric currents that have been measured;

FIG. 8 shows an example of telluric current induction fields andtelluric currents that have been measured; and

FIG. 9 shows an example of the pattern of change in telluric currentinduction field intensity.

BEST MODE FOR CARRYING OUT THE INVENTION

Explanation next regards the present invention with reference to theaccompanying figures.

FIG. 1 is a block diagram showing an embodiment of the presentinvention, and shows an earthquake prediction system that uses: mobileunits 1 such as a vehicle or a ship that are capable of movement on landor on sea; or existing fixed structures 2 that have been selected inadvance within the observation area, to collect observation data at amultiplicity of points within the observation area and predict, forexample, the seismofocal zone and time of occurrence of an earthquake.

In this case, the earthquake prediction system is provided with: mobileunit 1 in which, for example, magnetic force line sensor 11 and GPSposition detector 12 are mounted and which transmits observation data toearthquake prediction center 4; existing fixed structure 2 in whichmagnetic force line sensor 1 1 and communication equipment 14 have beeninstalled; communication network 3 for transmitting observation data toearthquake prediction center 4; and earthquake prediction center 4 forpredicting earthquakes based on the observation data of a multiplicityof points within the observation area.

Mobile unit 1 is vehicle 1-1 or ship 1-2 that moves within theobservation area and that carries: magnetic force line sensor 11 thatsupplies magnetic field data that indicate the intensity and directionof a line of magnetic force; GPS position detector 12 that receivesradio waves of a GPS satellite and that supplies position data; as wellas data transmitter 13 that transmits observation data to earthquakeprediction center 4.

When the mobile unit carries a car navigation system, the position dataof the car navigation system can be used and GPS position detector 12can therefore be omitted.

The observation data may be transmitted in real time, or a data storageapparatus may be provided for recording the observation data. It goeswithout saying that the observation data may also include, in additionto magnetic field data and position data, data indicating theobservation time.

Setting the observation data for automatic transmission at observationpositions and times that have been set in advance allows a reduction ofthe burden imposed on human operators.

In addition, effective observation data can be obtained if the entireobservation area is observed by mesh coverage. Mesh coverage is acovering method that is frequently used in radio-wave checks for mobiletelephones and involves preparing a map in advance of the region that isto be covered, casting lines in a mesh pattern, and then traveling in amesh pattern along these lines.

Existing fixed structures 2 that can be considered include:electrical/gas/water meters that are established in each residence andbusiness; vending machines that are established along roads; poles forpower lines and communication lines; poles for traffic signals;operation display apparatus that is installed at bus stops; and further,the buildings of mobile telephone base stations and PHS base stations.

Communication equipment 14 transmits either by cable or by radio toearthquake prediction center 4 the magnetic field data that are suppliedas the output of magnetic force line sensor 11 along with informationindicating the position of installation.

In this case, transmission may be carried out in real time, ortransmission may be implemented automatically at predeterminedobservation times.

The data transmission path can be easily secured when already existingfixed structure 2 is a pole for power lines or communication lines, apole for a traffic signal, or the building of a mobile telephone basestation or PHS base station. In addition, lower costs can be obtained ifan existing wireless communication means such as an emergency radiosystem is used.

When an installation such as an electrical/gas/water meter is used, theautomatic meter reading system may be used for transmission. If theoperation display apparatus that is installed at a bus stop is used, thevehicle operation management system may be used for transmission.Further, if vending machines are used, a system may be constructed fortransmitting the sales or stock information of the vending machinesalong with the magnetic field data.

Communication network 3 is an existing communication network such as amobile communication network that includes base stations or a satellitecommunication network that transmits by way of communication satellites.

Earthquake prediction center 4 includes: data receiver 41 for receivingobservation data by way of communication network 3 and an antenna; datastorage unit 42 for retaining and storing various data such asobservation data and map data; telluric current induction fieldestimation unit 43 for estimating telluric current induction fieldsbased on the observation data and map data that are retained and storedin data storage unit 42; telluric current estimation unit 44 forestimating the telluric currents based on the results of estimating thetelluric current induction field; telluric current induction fieldintensity change pattern generation unit 45 for accumulating transitionsof the telluric current induction field intensity over time andgenerating change patterns; and earthquake prediction unit 46 foranalyzing the estimation results for telluric currents and the changepatterns of the telluric current induction field intensity and thenpredicting the seismofocal zone, the seismic intensity, and the time ofoccurrence of an earthquake.

FIG. 2 shows a model of telluric current in the vicinity of seismofocalzone of an earthquake preceding the occurrence of the earthquake.

In this case, plate A and plate B are moving in mutually collidingdirections and thus press against each other. Point C at which the localpressure in the boundary plane between plate A and plate B is buildingis the seismofocal zone.

At this seismofocal zone C, massive stress is concentrated and anextremely high-stress state is in effect, and this stress graduallyrises with movement of the plates. During this state, it is assumed thatvoltage is generated by the piezoelectric effect in seismofocal zone C,and that charge within the rock mass flows into seismofocal zone C.

It is further assumed that the flow of charge within the rock mass(telluric current) follows points having good conductivity within therock mass and flows from each direction like rivers. Normally, sincemost seismofocal zones are underground, most of the charge flowsunderground and it is assumed that the charge rarely flows on theearth's surface.

It is hypothesized that immediately before the rock mass of seismofocalzone C fractures, the telluric currents rise with increasing speed, andsimultaneously with the fracturing of the rock mass, the piezoelectricvoltage vanishes with the release of stress and the telluric currentsinstantly disappear.

The telluric currents therefore occur and change as a precursor of anearthquake, and observation of the direction and intensity of thetelluric currents therefore enables prediction of an earthquake.

Since telluric currents do not flow on the earth's surface, directdetection of these currents is problematic, but induction fields thatare caused by telluric currents (telluric current induction fields) dooccur on the surface, and detection of the direction and intensity ofmagnetic fields on the surface therefore enables prediction of thedirection and intensity of a telluric current induction field.

The simplest method of observing a telluric current induction field isto observe the direction indicated by a magnetic needle. Under theinfluence of a telluric current induction field, a magnetic needleindicates a direction that diverges from the direction of normalterrestrial magnetism, and in an environment that is free of magnetismother than terrestrial magnetism and the telluric current inductionfield, a magnetic needle therefore enables the simplest and mosteconomical observation.

A second method allows more precise observation than a magnetic needlethrough the use of a magnetic force line sensor.

A third method enables even greater accuracy by combining the use of amagnetic force line sensor and a GPS position detector.

Alternatively, the combined use of a magnetic needle and a GPS positiondetector can obtain effective data for earthquake prediction. North asindicated by a magnetic needle does not align with true north, and it isfurther well known that this magnetic north shifts slightly every year.Thus, true north is found by means of a GPS satellite, and throughconstant observation of the difference from north as indicated by amagnetic needle, effective data for earthquake prediction can beobtained.

However, in order to raise the accuracy of observation data of telluriccurrent induction fields, the magnetic field noise component that isgenerated by factors other than telluric current must be eliminated fromthe observation data.

Magnetic field noise that occurs due to factors other than telluriccurrent principally arises from the following sources:

Magnetic fields that are generated by the direct current that flows inoverhead power lines at observation points that are close to railwaylines. Changes in such magnetic fields are characteristically short-termmicro-changes, with the intensity of the magnetic field increasing as atrain approaches and decreasing as a train moves away.

Geomagnetic storms caused by the Dellinger phenomenon that accompaniessolar activity. These disturbances characteristically occur anddisappear in short time intervals.

Magnetic fields that occur due to subterranean metal ores. These fieldsare characterized by constant fixed levels.

In order to eliminate the magnetic field noise component that isproduced by such factors other than telluric current, the magnetic fieldcan be observed at fixed intervals at fixed observation points, thecharacteristics of the change patterns in these magnetic fieldsanalyzed, and the magnetic field noise component then extracted andremoved by software.

FIG. 3 shows the earthquake prediction operations of earthquakeprediction center 4.

First, telluric current induction field estimation unit 43: removes themagnetic field noise component at the observation point from observedmagnetic field data (Step 101); then, as shown in FIG. 4, finds theamount of divergence from true north of the direction of the magneticfield at the observation point, from which the magnetic field noisecomponent has been eliminated (Step 102); and estimates telluric currentinduction field N2 based on the vector difference between observedmagnetic field N1 from which the magnetic field noise component has beeneliminated and geomagnetic vector N that has been corrected to truenorth (Step 103). Then, as shown in FIG. 5, the results are plotted on amap (Step 104).

Telluric current estimation unit 44 next connects the points on a map atwhich abnormalities in terrestrial magnetism have been recognized asshown in FIG. 5, and further, estimates the telluric current based onthe right-handed screw rule (Step 105).

Telluric current induction field intensity change pattern generationunit 45 collects past data of the telluric current induction fieldintensities at specific observation points and generates a telluriccurrent induction field intensity change pattern that shows change overtime (Step 106).

Earthquake prediction unit 46 analyzes the telluric current inductionfield intensity change patterns and the distribution of telluriccurrents that have been estimated by telluric current estimation unit44, searches for unnatural regions such as points where the telluriccurrents are concentrated, and thus estimates seismofocal zones.Earthquake prediction unit 46 further compares and collates the telluriccurrent induction field intensity change pattern that has been generatedwith past telluric current induction field intensity change patterns toestimate the time of occurrence and seismic intensity of an earthquake(Step 107).

As an example, when telluric current induction fields and telluriccurrents are plotted on a map of an observation area as shown in FIG. 6,the seismofocal zone can be estimated to be at point at which thetelluric currents within the observation area are concentrated, and alarge-magnitude earthquake can be estimated at a shallow layer directlybelow the observation area.

Further, when the telluric current induction fields and telluriccurrents are plotted on a map of the observation area as shown in FIG.7, the seismofocal zone can be estimated at a shallow layer in aVicinity outside the observation area.

When the telluric current induction fields and telluric currents areplotted on a map of the observation area as shown in FIG. 8, theseismofocal zone can be estimated in a remote shallow layer outside theobservation area, or in a plurality of close shallow layer points.

FIG. 9 shows an example of the pattern of change in telluric currentinduction field intensity. In this case, the telluric current inductionfield intensity is a relative value.

Typically, at a point close to the limit of elasticity that immediatelyprecedes the breakdown of the rock mass of a seismofocal zone, thetelluric current rises rapidly with the rapid rise in piezoelectricvoltage. A stagnation of telluric current is then observed thataccompanies the piezoelectric voltage saturation that immediatelyprecedes plastic deformation, following which, the piezoelectric voltagevanishes with the release of pressure that is simultaneous with thebreakdown of the rock mass, and the telluric current also disappearsinstantaneously.

In addition, the transition in telluric current over time is specifiedonly by the plasticity of the rock mass and relative vector speed of thetwo plates and has no relation to the distance from the observationpoints to the seismofocal zone; and since the telluric current inductionfields are generated by telluric currents, observing the transition intelluric current induction field intensity over time by fixed-pointobservation enables an estimation of the transition of telluric currentsover time.

In this case, storing past telluric current induction field intensitychange patterns of the environs of a seismofocal zone that occurs in aspecific identical plate boundary plane enables extraction of telluriccurrent induction field intensity change patterns up to immediatelypreceding the plastic deformation (occurrence of an earthquake) of theseismofocal zone. Accordingly, if the plates of an estimated seismofocalzone that is under observation can be specified, comparison andcollation with past telluric current induction field intensity changepatterns enables the estimation of an estimated time and seismicintensity until the plastic deformation of the rock mass (occurrence ofthe earthquake).

In addition, transition points of a curve function that indicates changein the telluric current induction field intensity can be set and thetime until the plastic deformation of the rock mass (earthquakeoccurrence) then estimated based on the telluric current induction fieldintensity at a point close to the limit of elasticity of the rock mass.Further, the maximum value that is reached by the telluric currentinduction field intensity can be estimated and the equivalent seismicintensity then estimated according to this maximum value.

In the foregoing explanation, magnetic force line sensors are installedin vehicles, ships, and existing fixed structures and magnetic fielddata are collected for each point within the observation area, but asanother working example, magnetic force line sensors and GPS positiondetectors may be incorporated into mobile telephones or portableterminals, which may then use their own communication capabilities totransmit observation data. In such a case, the observation data may beperiodically transmitted automatically, and if transmission fees are notcharged, observation data can be collected from many points over a widerange without imposing any financial burden on users.

Alternatively, if acceleration sensors are installed together withmagnetic force line sensors on existing fixed structures and observationdata then transmitted automatically when the acceleration sensors detectearthquake motion, magnetic field data can be collected at the time ofoccurrence of foreshocks that precede a main shock, whereby dataeffective for earthquake prediction can be obtained.

Still further, if acceleration sensors together with magnetic force linesensors are incorporated in mobile units such as vehicles or ships aswell as in mobile telephones or portable terminals, observation data maybe automatically transmitted when the acceleration sensors detect astationary state of at least a fixed time interval.

As described in the foregoing explanation, earthquakes can be accuratelypredicted by collecting magnetic field data at a multiplicity of pointswithin an observation area, estimating telluric current inductionfields, estimating telluric currents based on the telluric currentinduction fields that have been estimated, and then analyzing theseestimation results.

1. An earthquake prediction method wherein: telluric current inductionfield vectors and telluric currents are estimated based on vectordifferences between observed magnetic field vectors of magnetic fieldsthat are observed within an observation area and a geomagnetic vector;and change over time of the telluric currents and a state of telluriccurrents within said observation area are compared and collated withpast patterns of change over time of the telluric currents and a stateof the telluric currents to estimate a seismofocal zone, time ofoccurrence, and seismic intensity of a seismic event.
 2. An earthquakeprediction method according to claim 1, wherein: a magnetic field noisecomponent at observation points is eliminated from observed magneticfields; an amount of divergence of a direction of a magnetic fields froma direction of true north at observation points from which said magneticfield noise component has been eliminated is found; and said telluriccurrent induction field vectors are estimated based on vectordifferences between observed magnetic field vectors from which saidmagnetic field noise component has been eliminated and a geomagneticvector that has been corrected to true north.
 3. An earthquakeprediction method according to claim 2, wherein: said estimated telluriccurrent induction field vectors are plotted on a map; and said telluriccurrents are estimated by both joining points on the map at whichgeomagnetic abnormalities are recognized and applying Ampere'sright-handed screw rule.
 4. An earthquake prediction method according toclaim 1, wherein: said estimated telluric current induction fields areplotted on a map; and an area in which said estimated telluric currentsare concentrated is estimated to be a seismofocal zone.
 5. An earthquakeprediction method according to claim 1, wherein: past data of telluriccurrent induction field intensities of said seismofocal zone that hasbeen estimated in claim 4 are gathered and a telluric current inductionfield intensity change pattern that indicates change over time isgenerated; and this pattern is then compared and collated with pasttelluric current induction field intensity change patterns that havebeen stored to estimate said time of occurrence and seismic intensity ofa seismic event.
 6. An earthquake prediction system that uses theearthquake prediction method according to claim 1; said earthquakeprediction system comprising: mobile telephones or mobile units such asvehicles or ships, each unit carrying: a magnetic force line sensor forsupplying as output magnetic field data that indicate a direction andintensity of lines of magnetic force; a GPS position detector forreceiving radio waves of a GPS satellite and supplying as outputposition data that indicate position; and a data transmitter fortransmitting said data; and an earthquake prediction center forcollecting said data of various points that are transmitted by saidmobile units or said mobile telephones that travel within an observationarea and then implementing earthquake prediction.
 7. An earthquakeprediction system according to claim 6, said earthquake predictioncenter comprising: a data receiver for receiving data that have beentransmitted from said mobile telephones or said mobile units by way of acommunication network and antenna; a data storage unit for retaining andstoring various data such as map data and data that have been receivedby said data receiver; a telluric current induction field estimationunit for estimating telluric current induction fields based on map dataand data that have been retained and stored in said data storage unit;telluric current estimation unit for estimating telluric currents basedon said telluric current induction fields that have been estimated; atelluric current induction field intensity change pattern generationunit for accumulating transitions over time of said telluric currentinduction field intensities and then generating change patterns; and anearthquake prediction unit for analyzing said telluric currents thathave been estimated and said change patterns of said telluric currentinduction field intensities to estimate a seismofocal zone, seismicintensity, and time of occurrence of a seismic event.
 8. An earthquakeprediction system according to claim 6, wherein, when said mobile unitis provided with a car navigation system, position data of said carnavigation system is used instead of data from said GPS positiondetector.
 9. An earthquake prediction system according to claim 6,wherein: said magnetic force line sensor and communication equipment areinstalled in preselected existing fixed structures within theobservation area; and said communication equipment transmits magneticfield data output of said magnetic force line sensor and informationindicating installation positions to said earthquake prediction centerby way of an existing communication network.
 10. An earthquakeprediction system according to claim 6, wherein: said magnetic forceline sensor and GPS position detector are incorporated in a mobiletelephone or a mobile unit; and said mobile telephone uses its owncommunication capabilities to transmit observation data to saidearthquake prediction center.
 11. An earthquake prediction systemaccording to claim 9, wherein an acceleration sensor is provided, andsaid magnetic field data are transmitted when said acceleration sensordetects earthquake motion.
 12. An earthquake prediction system accordingto claim 6, wherein an acceleration sensor is provided and said magneticfield data are transmitted when said acceleration sensor detects astationary state of at least a fixed time interval.
 13. An earthquakeprediction method according to claim 2, wherein: said magnetic fieldnoise component is change in magnetic field that is observed at fixedtime intervals at a fixed observation point; and said magnetic fieldnoise component is eliminated by analyzing characteristics of a patternof this change and then extracting the magnetic field noise component.14. An earthquake prediction method according to claim 2, wherein saidtelluric currents are estimated by means of Ampere's right-handed screwrule based on said estimated telluric current induction field vectors ofa plurality of points.
 15. An earthquake prediction method according toclaim 14, wherein said telluric currents are estimated by means ofAmpere's right-handed screw rule based on said estimated telluriccurrent induction field vectors of a plurality of points that form aloop.